High performance door latch mechanism for sliding doors

Abstract

A latch mechanism for securement to an edge portion of a closure element, and more particularly, but not exclusively, a sliding door. The door latch mechanism has a housing with a slide member having keeper engaging hook members to engage a keeper secured to a door jamb for locking and unlocking the door within a door frame. The slide member is guided along a straight axis and is connected to a finger engaging knob to displace it along that axis to lock and unlock the mechanism with the keeper. The slide member has one or two elongated through bores extending co-extensively with the straight axis and a load transfer pin-like member extends through the bores and connected on opposed sides to transfer lateral loads applied to the slide member to the door latch mechanism housing and door stile.

I claim: 
     
       1. In combination a latch mechanism adapted for securement to an edge portion of a sliding door, said latch mechanism comprising a housing having a slide member with one or more keeper engaging elements to engage a keeper member securable to a sliding door jamb for locking and unlocking said sliding door within a frame, guide means in said housing for guiding said slide member along a straight axis, finger engaging means connected to said slide member and accessible from outside said housing for displacing said slide member along said axis to move said keeper engaging means to a locking or unlocking position, said slide member having an elongated through bore extending co-extensively with said straight axis, said housing being secured to an inner side wall of a door stile of said sliding door, said keeper member being secured to an inner side surface of said door jamb in alignment with said keeper engaging element, said door stile having opposed parallel outer and inner metal side walls, and a load transfer rod extending through said inner and outer metal side walls of said sliding door stile and secured in a back wall of said housing, said load transfer rod being concealed on said outer side wall of said stile, said load transfer rod extending through said bore of said slide member in sliding contact with at least a side edge of said bore in abutment therewith to resist separating lateral forces applied to said slide member by forces entry loads. 
     
     
       2. A latch mechanism as claimed in claim 1 wherein said slide member is an elongated flat metal plate having opposed parallel elongated side edges, said one or more keeper engaging elements being constituted by one or more hook fingers extending from an outer one of said side edges and formed integral with said metal plate, said guide means being guide members disposed in friction contact with said side edges. 
     
     
       3. A latch mechanism as claimed in claim 2 wherein said housing has a side opening for receiving a keeper housing having one or more engageable slots in a front wall for engagement by said one or more hook fingers. 
     
     
       4. A latch mechanism as claimed in claim 2 wherein there are two of said elongated through bore, said through bores being slots, each slot being aligned with a longitudinal axis of said metal plate and positioned in a respective one of opposed end portions thereof, said load transfer rod extending through said bore being a bolt fastener, there being a bolt fastener extending through each said slots. 
     
     
       5. A latch mechanism as claimed in claim 2 wherein said door stile is an extruded hollow style of rectangular cross-section and of material capable of resisting required load. 
     
     
       6. A latch mechanism as claimed in claim 5 wherein said bolt fasteners have a bolt head disposed over said outer side wall of said stile and concealed by an outer handle plate, and at least a threaded free end section of said bolt being threadably engaged in threaded bores located in an inner surface of said lock mechanism housing. 
     
     
       7. A latch mechanism as claimed in claim 1 wherein said finger engaging means is a finger engageable slide member slidingly secured over an outer surface of said lock mechanism housing, a connecting bolt secured to said finger engaging member and said slide member, said connecting bolt extending through a slot in said outer wall of said lock housing and aligned with said straight axis of said slide member. 
     
     
       8. A latch mechanism as claimed in claim 1 wherein said keeper member is a hollow keeper housing having opposed side walls, a connecting rear wall, and a retention front wall, one or more slot openings in said front wall for receiving said one or more keeper engaging elements therein, said side walls being reinforcing walls for said front wall, said front wall defining retaining wall portions adjacent said one or more openings for engagement by hook fingers of said side plate. 
     
     
       9. A latch mechanism as claimed in claim 8 wherein there are two of said keeper engaging elements received in a respective one of two said slot openings in said keeper front wall, and holes in said connecting rear wall for receiving connecting fasteners therethrough from said slot opening or fastener receiving openings in said front wall, said connecting fasteners being concealed inside said hollow keeper housing. 
     
     
       10. A latch mechanism as claimed in claim 9 wherein said keeper housing is formed from stainless steel sheet material, at least one of said holes in said rear wall being a slotted adjustment hole for adjusting the position of said housing. 
     
     
       11. A latch mechanism as claimed in claim 2 wherein said lock mechanism housing is casted from plastics material and has a handle secured thereto, said guide members being formed by opposed guide walls, said hook fingers extending through a keeper receiving opening formed in an outer edge wall.